With the judgement of the case being delivered less than a week before the end of the coming financial year, its tax profiles could be significantly affected.

In a significant win for Amazon.com Inc, the world’s biggest online retailer has won more than $1.5 billion in a tax dispute case with the Internal Revenue Service over transactions that happened a decade ago, concerning a unit in Luxembourg.

U.S. Tax court judge, Albert Lauber rejected a variety of IRS arguments, since he found that on several occasions the agency had acted capriciously, had abused its position as well as its discretion.

With Amazon wining the case so late in the year, its ultimate tax liability from this decision is not immediately clear.

Amazon has said winning this case could boost its federal tax liability by $1.5 billion plus interest. The case involved transactions from 2005-2006. Its tax profile has been “significant[ly]” affected by winning this case.

In 2016, the one retailer made a profit of $2.37 billion on a turnover of $136 billion.

As per Colin Sebastian, an analyst at Baird Equity Research, Lauber’s decision “should shield Amazon from potentially significant tax obligations to the IRS covering years beyond the ones covered in the lawsuit”.

The IRS case revolved around Amazon’s “transfer pricing,” wherein various units of the company transact with one another.

Amazon’s argument stated that the IRS had overestimated the value of “intangible” assets, including trademarks and software, it had transferred to Amazon Europe Holding Technologies SCS, its Luxembourg unit.

According to Lauber, Amazon, through its “Project Goldcrest,” planned to have the “vast bulk” of income from its European businesses taxed in Luxembourg at a “very low rate.”

The IRS countered Amazon’s argument saying the company’s dealings were not all done at “arm’s length,” thus suggesting that Amazon has manipulated to lower its domestic tax bill.

“This is good for everybody, not just Amazon,” said Michael Pachter, a Wedbush Securities analyst who has practiced tax law. “It reaffirms that the tax law permits wholly-owned subsidiaries can license intellectual property” as Amazon did. “Totally legal, totally legal.”

For Amazon wining this case has also resulted in a hike up of its European Tax bill, if European authorities were to decide that prior rulings by Luxembourg tax officials amounted to improper “state aid” that gave it an unfair advantage over rivals.